TM 11-2057A Test Set TS-27B/TSM 17 December 1973 reprint of 1952 Oct document "These instructions are published for the information and guidance of the personnel to whom the equipment is issued. They contain information on the operation, organizational maintenance, and field maintenance of the equipment, as well as a discussion of the theory of operation. They apply only to Test Set TS-27B/TSM. Appendix I contains a list of current references, including supply catalogs, technical manuals, and other available publications applicable to the equipment. Appendix II contains an identification table of parts.